At the nearby town of Plansk 10 days ago, Stainislaw Kania, the new leader of Communist Poland and First Secretary of the party, met with a group of party members working at a chemical factory. What happened there shows that, beneath a calmer surface, there are still working forces that could blow Poland apart and bring on a world crisis.

The meeting took place at the factory in a small room jammed with workers who filled every available seat and stood in the doorways. Kania was introduced by the local party leader. Before opening the floor to questions, the local leader had a complaint to pass on to the First Secretary. He felt the party leadership was moving too slowly in purging corrupt officials.

The workers started to pop questions from the floor. One, named Kowalski, wanted to know why government ministers were also members of the party politburo and secretariat. Wasn't one job hard enough?

A woman worker, named Wanda Machon, said the party unit in the factory had voted for resolutions demanding more internal democracy in electing party officials. She wanted to know what action had been taken on the resolutions.

An engineer asked for comment on the notion that all party officials should be elected. He said, "The elections should not just be confined to lower echelons. It is not there that the trouble began."

After listening to these and many other complaints, Kania replied. He said the country faced a major economic crisis. He said the party was the "only force" that could bring the country out of the crisis. He said reforms were under way and would continue. But he acknowledged the way ahead was hard. He said: "Today it is difficult to be a member of the party. It is also difficult to be First Secretary of the party."

Meetings like the one in Plonsk are going on everyday all over Poland. For there has been a displacement of the struggle that pitted the independent trade union, Solidarity, against the party leadership. Now the struggle has moved, largely behind closed doors, to the center of the party.

The younger members -- and about half of the 3.5 million members are under 30 -- are putting pressure on the leadership. In many areas they have established autonomous party units. In some cases they have forced all their officials to resign. In others they have passed resolutions calling for sweeping change. Among other things, these resolutions call for free election of party officials, a limit on the number of terms any party official can serve and a rigid separation between the party and the government. To effect these changes, the younger members have demanded a Party Congress.

Kania and his associates have met the challenge by temporizing. They have promised a Party Congress -- but not until spring. They have removed some officials, but kept many in office. Their theory, apparently, is that in time the ferment will cease. Poland, after all, has had a tough year, and the period of rest would be welcome. But if the pressure does not ease, the Kania is in a very weak position.

For one thing, the economy truly is in bad shape. Food, especially meat, is in short supply, and there will have to be cuts in consumption. Critical components of industrial activity -- notably energy and transport -- are not available, and some plants will have to be shut down. The balance of payments is so much in deficit -- mainly because of reduced exports as a result of declining coal production -- that the country will have to borrow massively just to pay its current debts. So, as a practical matter, Kania has only blood, sweat and tears to offer.

A leader with great personal authority could perhaps evoke a willingness to sacrifice. But Kania is a dumpy man without magnetism. He speaks so poorly that when his speeches are televised, they are read by a professional announcer. He is so little known in the country at large that many Poles who did not recognize the announcer, thought he was Kania.

To be sure, Kania currently enjoys the confidence of the Russians. He has good relations with both Lech Walesa, the head of Solidarity, and the Polish Premate, Cardinal Wyszynski. Presumably, they will all do what they can to hold the pressure down.

But the combination of economic distress and party ferment is hard to contain. It is touch and go whether Kania can last out the next few months. Any successor -- and the one most mentioned is former Interior Minister Mieczyslaw Moczar -- would probably use harsh methods. But a show of force might well provide the blowup that would oblige the Russians to intervene -- with terrible consequences for everybody.